o Ganglia are found near the CNS from T1 – L2, but innervation is widespread

o Two sets of paravertebral ganglia(lateral to spinal cord) and one of prevertabral (in front of spinal cord)

o White ramus communicans contains the axons of the preganglionic nerves and connects segmental nerve with preganlionic chains, T1-L2 ONLY

Parasympathetic

Anabolic (accumulation of energy stores)

Increase in gut motility, vasodilation of vessels in the gut (kind of opposes the sympathetic)

Enteric: Largenumber of neurons present within the walls of the intestine that can controlthe intestinal motility independent of the CNS; regulated by sympathetic andparasympathetico In the gut, the neurons get two kinds of input, from both the parasympathetic and sympathetic

In the prevertebral region, ACh is the neurotransmitter of the preganglionic sympathetic nerves, and the postganglionic nerves release NE in the gut

The parasympathetic nerves go straight to the gut and release ACh there

Preganglionic

Goes from origin to ganglia; (myelinated → white)

Postganglionic

goes from ganglia to target; no myelin sheath (→ gray)

Hollow organ

Visceral organ that is a hollow tube or pouch or that includes a cavity that serves a vital function

Prevertebral

Found in front of the vertebra, one prevertebral sympathetic chain ganglia, innervates the gut

o Preganglionic nerves move down within the sympathetic chain and then “bolt” without innervating the paravertebral ganglion cells → innervate the prevertebral ganglia and adrenal medulla (these preganglionic nerves are called splanchnic nerves)

Intramural

Occurring or situated within the walls of a cavity or organ

Describe the organization of the PNS interms of somatic/autonomic components

The somatic (voluntary) system responds to the external environment (sensory input), and its motor target is skeletal muscle.

The autonomic (visceral) system is automatic and its sensory input is

internal. Its efferent targets are smooth muscle, cardiac muscle, and glands; smooth muscle and cardiac muscle are associated with the hollow organs of the body

Name the cell types and functions of cells,all or part of which are located in the PNS

Somaticmotor neurons are used to induce voluntary movement and consist of a cell bodyin the CNS, nerve in the PNS with the synapse/terminal at the target. The autonomic system has a preganglionic neuron with its cell body in the CNS. The axon extends into the PNS and synapses/terminates at a ganglion where the postganlionic neuron’s cell body resides. The axon of that postganglionic neuron then extends to the target (smooth muscle, cardiac muscle, or glands). Autonomic neurons are either sympathetic or parasympathetic, and the easiest way to tell which is which is to look at the location of the preganglionic neuron. The preganglionic neurons of the sympathetic system emerge from T1-L2/3 while the preganglionic neurons of the parasympathetic system emerge from S2-S4. Another difference is the location of the cell body of the postganglionic neurons. If it lies near the spinal cord, then it is sympathetic. Parasympathetic postganglionic neuron cell bodies, on the other hand, lie near or within the target.

Describe all the possible cell types whoseaxons are located in peripheral nerves, their functions, and the location oftheir cell bodies